Preparation and Optical Properties of Epitaxial Thin Films of Some II-VI Semiconducting Compounds

摘要

The work describes mainly the preparation and optical properties of epitaxial thin films of some II-IV semiconducting compounds. In addition optical modulation experiments on both thin film and bulk samples are reported. Epitaxial thin films of CdTe, HgTe, the alloy system CdxHg1-xTe, and CdSe were prepared by a flash evaporation technique on BaF2 substrates. The effects of various deposition parameters on the electron diffraction and optical structures of CdTe and CdSe were analyzed in detail. Optical transmission measurements on the epitaxial thin films were made at room and liquid nitrogen temperatures in the spectral region from 2 to 6 eV. Two novel approaches of optical modulation methods were pursued: piezo-transmission on Ge and CdTe polycrystalline films and electroreflectivity on bulk CdTe using an integral sandwich technique. Both methods were used down to liquid helium temperatures.